Copper conductive coating composition

Abstract

A copper-type conductive coating composition which comprises: (A) a copper powder, (B) a coating binder resin, and (C) at least one number selected from the group consisting of salicylic acid, its specific derivatives, and benzotriazolecarboxylic acid hydrazides. The copper-type conductive coating composition provides a conductive coating layer having excellent initial conductivity and capable of maintaining the level of it stable over a long period of the time.

We claim: 
     
       1. A copper conductive coating composition which comprises: (A) from 10 to 90% by weight of a copper powder,   (B) from 10 to 90% by weight of a coating binder resin, and   (C) from 0.01 to 5% by weight of at least one member selected from the group consisting of salicylic acid or its derivatives represented by the formula: ##STR4## wherein each of R 1  and R 2  is a hydrogen atom or a C 1-4  alkyl group, and X is a --COOH group, a --COH=NOH group, --CONHNH 2  group, a --CONH 2  group or a --CH=NOH group, salicyclic acid dreivatives represented by the formula: ##STR5## wherein each of R 3  to R 5  is a hydrogen atom or a C 1-8  alkyl group, R 6  is a hydrogen atom or a C 1-8  hydrocarbon group having a valency of n, and n is an integer of from 1 to 4, and benzotriazolecarboxylic acid hydrazides represented by the formula: ##STR6## wherein R 7  is a carboxylic acid residue having a valency of m, and m is an integer of from 1 to 4.   
     
     
       2. The copper conductive coating composition according to claim 1, wherein the copper powder has a hydrogen loss of at most 0.6% by weight. 
     
     
       3. The copper conductive coating composition according to claim 2, wherein the copper powder has a hydrogen loss of at most 0.2% by weight. 
     
     
       4. The copper conductive coating composition according to claim 1, wherein the copper powder is treated with a carboxylic acid. 
     
     
       5. The copper conductive coating composition according to claim 4, wherein the carboxylic acid is citric acid. 
     
     
       6. The copper conductive coating composition according to claim 1, wherein component (C) is a salicylic acid or its derivative of the formula I or II. 
     
     
       7. The copper conductive coating composition according to claim 6, wherein the salicylic acid derivative is a bissalicyloylhydrazine of the formula II. 
     
     
       8. The copper conductive coating composition according to claim 1, wherein a 9,10-dihydro-9-oxa-10-phsophaphenanthrene-10-oxide is used in combination with component(C).